1. Field of the Invention
This invention relates to liquid spray nozzles and more particularly to a spray nozzle having openings angled towards each other to form a triangular spray pattern and a mixing chamber shaped to reduce turbulence and clogging.
2. Description of the Related Art
Spray nozzles for generating streams of liquid are well known as seen from U.S. Pat. No 6,322,008 to Mark Aker, et al, which is hereby incorporated by reference. This patent describes a nozzle having at least two openings on its face, spaced apart from one another and angled towards each other such that two individual streams cross each other at a point distant from the face of the nozzle. A non-atomized, pressurized stream passes through each opening and meets at an intersection point, forming a flat, triangular pattern. The nozzle is useful in spraying polyester gelcoat applications and reduces emissions of volatile organic compounds.
Often, the materials sprayed using this nozzle or similar nozzles are very viscous or harden quickly. For example, boat hulls are often formed by spraying resins over a mold. In some applications, fillers are added to the resin such as calcium sulfate, calcium carbonate and aluminum trihydrate to improve fire retardency. These fillers further thicken the resins. The viscosity of these liquids and their fast hardening times often cause problems with the nozzle such as clogging. Other than the general problem of clogging of the nozzle openings, the flow of the material within the nozzle causes problems. Turbulence within the nozzle creates dead-spots where the material being sprayed may sit without passing through the nozzle. After time, that material may harden, reducing the area within the nozzle, leading to different dead spots. Eventually, more material may harden within the nozzle, leading to reduced flow. Finally, part of the hardened material may break away and clog the openings in the nozzle or may exit the nozzle and attach itself to the target object. As this build-up occurs, the spraying operation must be stopped, the nozzle removed and cleaned or replaced, and the spraying operation restarted. This stop/restart operation reduces the efficiency of the application and may affect the overall quality of the spray by creating runs or uneven applications.
What is needed is a nozzle that will provide all the advantages of the prior nozzles while reducing accumulation within the nozzle, hence reducing clogging and the need for replacing or cleaning the nozzle during the spray operation.